Eating too many so-called 'American-style' portions puts us more at risk of cancer, heart disease and diabetes.
That's according to the World Cancer Research Fund (WCRF).
Shrink it
It's well-known that eating unhealthily puts people at risk of serious diseases later in life.
But now the size of our portions is also being blamed.
There's a growing trend for all-you-can-eat restaurants and super-size packets of crisps and chocolate bars.
The WCRF says we're all eating more like Americans, and our portion sizes have sometimes doubled or even tripled.
They say the sensible thing to do is simply stop eating when you're full.
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